<template>
  <div class="widthResize h100">
    <div ref="dragLine" class="resize" title="收缩侧边栏">
      <i class="el-icon-s-unfold"></i>
    </div>
  </div>
</template>

<script>
export default {
  name: "widthResize",
  methods:{
    dragControllerDiv: function () {
      var resize = document.getElementsByClassName('resize');
      var left = document.getElementsByClassName('treeDiv');
      var mid = document.getElementsByClassName('tableDiv');
      var box = document.getElementsByClassName('tab-switch');
      for (let i = 0; i < resize.length; i++) {
        // 鼠标按下事件
        resize[i].onmousedown = function (e) {
          //颜色改变提醒
          resize[i].style.background = '#818181';
          var startX = e.clientX;
          resize[i].left = resize[i].offsetLeft;
          // 鼠标拖动事件
          document.onmousemove = function (e) {
            var endX = e.clientX;
            var moveLen = resize[i].left + (endX - startX); // （endx-startx）=移动的距离。resize[i].left+移动的距离=左边区域最后的宽度
            var maxT = box[i].clientWidth - resize[i].offsetWidth; // 容器宽度 - 左边区域的宽度 = 右边区域的宽度

            if (moveLen < 32) moveLen = 32; // 左边区域的最小宽度为32px
            if (moveLen > maxT - 150) moveLen = maxT - 150; //右边区域最小宽度为150px

            resize[i].style.left = moveLen; // 设置左侧区域的宽度

            for (let j = 0; j < left.length; j++) {
              left[j].style.width = moveLen + 'px';
              mid[j].style.width = (box[i].clientWidth - moveLen - 10) + 'px';
            }
          };
          // 鼠标松开事件
          document.onmouseup = function (evt) {
            //颜色恢复
            resize[i].style.background = '#d6d6d6';
            document.onmousemove = null;
            document.onmouseup = null;
            resize[i].releaseCapture && resize[i].releaseCapture(); //当你不在需要继续获得鼠标消息就要应该调用ReleaseCapture()释放掉
          };
          resize[i].setCapture && resize[i].setCapture(); //该函数在属于当前线程的指定窗口里设置鼠标捕获
          return false;
        };
      }
    },
  },
  mounted() {
    this.dragControllerDiv();
  }
}
</script>

<style lang="less" scoped>
.widthResize{
  font-size: 14px;
  height:100%;
  width:100%;
  /*拖拽区div样式*/
  .resize {
    cursor: col-resize;
    //background-color: #d6d6d6;
    color:#d6d6d6;
    background-color:transparent;
    width: 0px;
    //height:50px;
    font-size:18px;
    font-weight:bold;
    position:absolute;
    top:50%;
    //height: 100%;
    //color: white;
  }
  .resize:hover{
    color:#d6d6d6;
  }
}
</style>
